1. Field of the Invention
The present invention relates to an electric connector and particularly to a connector having a withdrawal preventing locking mechanism.
The recent electronic equipment having high-speed data transferring ability demands coaxial connectors to be equipped thereto to enable high-speed data transfer. For this purpose, coaxial connectors having improved insertion/drawing-out operation convenience and good withdrawal preventing ability have been provided.
However, such high-speed data transfer requirement requires a relevant electric cable to be thickened (outer diameter being enlarged) and such a thick cable having a heavy weight accordingly may apply a large tension force thereto, the large tension force causing the external force applied to the relevant connector to be increased accordingly.
The connector is required to provide a high electricity conducting reliability even when a large external force is applied to the relevant connector.
2. Prior Art
Japanese Laid-Open Patent Application No. 1-276576 discloses a connector having a withdrawal preventing mechanism for example as shown in FIGS. 1A, 1B and 1C. The connector consists of the plug 2 and socket 1. FIG. 1A shows the connector in a condition before the plug 2 is inserted into the socket 1. FIG. 1B shows the connector in a condition during the time the plug 2 is being inserted into the socket 1. FIG. 1C shows the connector in a condition where the plug-socket insertion is completed so that the locking between the plug 2 and socket 1 is established.
The plug 2 is provided with an insulating element 4 supporting a male contact 3 in the center of the plug 2; and a plug shell 5 provided around the insulating element 4. The plug shell 5 is provided with a groove 7 throughout the entire circumference thereof, the groove 7 being used to lock the plug 2 to the socket 1.
The socket 1 consists of a socket body including a cable supporting member 9 including an approximately cylindrical insulating element 8 and a metal shell 10; and a cylindrical slidable sleeve 11 provided around the socket body and forward/backward slidable.
The insulating element 8 supports a female contact 12 in the center thereof. The cable supporting member 9 is installed on a coaxial cable 14, to be connected to the circuit accompanied by the plug 2. The insulating element 8 is located at the front of the cable supporting member 9. The metal shell 10 having an approximately cylindrical shape is screwed onto and thus fixed to the cable supporting member 9.
An inserting portion 6 of the plug 2 is inserted into the front end of the metal shell 10. The metal shell is provided with slits creating a plurality of segments 16 inwardly transformable due to its elasticity. The slidable sleeve 11 is provided with an establishing portion 17 extending inside from the front-end (right in the figure) backwards (left in the figure), the inner diameter of which portion is smaller than the front-end outer diameter of the metal shell 10.
The socket 1 is formed as follows: The cable supporting member 9 is screwed onto and thus fixed to the metal shell 10; then the metal shell 10 is forward inserted into the slidable sleeve 11; and a ring spring 19 having the shape of the Greek letter .OMEGA. is installed on the slidable sleeve 11 using a spring installation groove 18.
In FIG. 1A, since the slidable sleeve 11 is located toward the rear of the metal shell 10, the segments 16 have not been transformed inwardly, that is, the segments are in the open state. As a result, the force required to be applied to the connector so as to insert the plug 2 into the socket 1 can be reduced, easy inserting being thus achieved.
After the operator inserts the plug 2 into the socket 1 so as to place the connector in a predetermined spatial state, the operator should cause the slidable sleeve 11 to slide forward so as to place the connector in the spatial state shown in FIG. 1C. Since the slidable sleeve 11 is provided with the establishing portion 17 as described above, the forward sliding of the sleeve 11 causes the segments 16 to move inside so as to be engaged with the metal shell securely. This engagement prevents (locks) the plug 2 from being drawn out from the socket 1.
If the operator intends to draw out the plug 2 from the socket 1, the operator should cause the slidable sleeve 11 to move backward. As a result, the engagement of the segments 16 with the metal shell 10 may be released and the plug 2 may be drawn out from the socket 1. Thus, the force required to be applied to the connector so as to draw out the plug 2 from the socket 1 can be reduced, easy drawing out being thus achieved.
However, a certain problem may occur in such a connector in the prior art, due to the construction where the plug 2 is directly locked to the socket 1. Accordingly, an external force applied to the connector almost directly affects the electrically conducting portion therein. The external force applied may be a large one due to the thickening the cable 14 as described above.
Concretely, some instability may appear in the electrically conducting portion between the male contact and female contact in the connector, the electrical conduct being thus degraded or ineffective. Further, in a case where the electrical circuit accompanied by the plug 2 is fixed on a circuit substrate or the like through soldering, the soldering connection may be ineffective due to the large external force being applied to the connector. Thus, the reliability may be reduced due to the thickening of the cable 14 in the prior art.